Atlas 3995 Chattering

[markba633csi]

The others may disagree with me but my feeling is you haven't gotten your hands on a decent cutting tool yet
It's quite possible that LMS is selling stuff that doesn't work. Certainly the one you are showing is not correct.
It looks like some kind of strange flycutter bit, but not what you need. The bit should have a (slightly) rounded nose for good finish
Look thru the PDF I posted and compare- you're at the mercy of someone else's skill- or lack of
You really need to grind- you can whip up a bit that will peel off metal like a bandit- like magic

 

[SouthernChap]

The others may disagree with me but my feeling is you haven't gotten your hands on a decent cutting tool yet
It's quite possible that LMS is selling stuff that doesn't work. Certainly the one you are showing is not correct.
It looks like some kind of strange flycutter bit, but not what you need
Look thru the PDF I posted and compare- you're at the mercy of someone else's skill- or lack of
You really need to grind- you can whip up a bit that will peel off metal like a bandit- like magic

I don't think so. I have cutters like that. It's a right hand knife tool. Nothing weird, just intended for general turning.

I can get a decent finish in EN1A and even a reasonable one in stainless (the fact that the stainless surface finish was decent, makes me guess it was 303) with a tool just like that. Certainly nothing as, um, exciting as the OP has shown!

They come a bit sharp out of the box and need a bit of a teensy radius put on with a stone but eh, they're okay.

 

[SouthernChap]

Yeah. That bit is not helping

Nah, the tool's probably fine. It's just a standard right hand HSS knife tool like you get in a lot of sets.

I've got one just like it and got much better finishes than the OP has shown.

 

[pontiac428]

What angle are you presenting the tool to the work at? Maybe try that tool with a little (15 deg) lead to it (rotating tool post CW as viewed from above, funky tool). A bit of rubbing on a sharpening stone to make the edges fingernail-shaving keen and a small nose radius at least equal to feed rate might help. And forgive me for even bringing it up, but your motor isn't wired to run reverse, is it?

 

[gedkins]

It won't even turn brass. Half hard plain brass. Looks like a ran 60 grit sandpaper over it.
I am just happy I got it for free.

 

[gedkins]

What angle are you presenting the tool to the work at? Maybe try that tool with a little (15 deg) lead to it (rotating tool post CCW as viewed from above). A bit of rubbing on a sharpening stone to make the edges fingernail-shaving keen and a small nose radius at least equal to feed rate might help. And forgive me for even bringing it up, but your motor isn't wired to run reverse, is it?

I have tried many alternate angles with no difference. The Atlas is a thread on chuck, if you run the lathe in reverse, you end up with a chuck rolling on the floor.

 

[pontiac428]

Ok, that's just wrong. You can turn brass with a shine using any edge on a broken drill bit in the tool holder.

Chuck up something round and put a dial indicator on it. With the power off, deflect the round object all different directions by hand and watch the dial. Is it steady against all but the hardest pressures, or is it a jiggly mess? Because I'm guessing the latter, unless your lathe is indeed running in reverse. That's the crux of the spindle bearing preload question. Then do the same thing with the indicator on the tool. Something has to be wobbly to get that result.

 

[Nutfarmer]

Obtain the book from the South Bend Company How To Run a Lathe. I think you can download it here. Next look up the postings here on how to grind a tool bit. It is well done and explains the process very well. Forget carbide on a small lathe while you are learning. Post a picture of your set up. Looks like the tool bit doesn’t have the proper clearance and is dragging not cutting. I have seen loose sloppy lathes cut with a correct bit.

 

[markba633csi]

Make a video! ( I still think it's the bit )
I will defend this poor little maligned Atlas till my last breath

We hold these Atlases (Atli?) to be self-evident

 

[gedkins]

@

Ok, that's just wrong. You can turn brass with a shine using any edge on a broken drill bit in the tool holder.

Chuck up something round and put a dial indicator on it. With the power off, deflect the round object all different directions by hand and watch the dial. Is it steady against all but the hardest pressures, or is it a jiggly mess? Because I'm guessing the latter, unless your lathe is indeed running in reverse. That's the crux of the spindle bearing preload question. Then do the same thing with the indicator on the tool. Something has to be wobbly to get that result.

I have tried that. If I put an indicator on the OD of the chuck and simply push across the diameter at the center I can deflect as shown.